✨ feat(vscode): ensureWorktreeFromRemote 从远端分支重建 worktree

Claude-Session: https://claude.ai/code/session_011cEyL6k351U2BzX1Qmygph

vscode/src/git/worktree.ts

@@ -34,7 +34,7 @@ export interface WorktreeOpts {
   branch: string
 }
 
-function runGit(workspaceRoot: string, args: string[], failLabel?: string): Promise<string> {
+export function runGit(workspaceRoot: string, args: string[], failLabel?: string): Promise<string> {
   return new Promise((resolve, reject) => {
     execFile('git', ['-C', workspaceRoot, ...args], { timeout: 30_000 }, (err, stdout, stderr) => {
       if (err) {
@@ -94,7 +94,7 @@ function parseWorktreePorcelain(stdout: string): Array<{ path: string, branch: s
   return entries
 }
 
-async function findLiveWorktreeForBranch(workspaceRoot: string, branch: string): Promise<string | undefined> {
+export async function findLiveWorktreeForBranch(workspaceRoot: string, branch: string): Promise<string | undefined> {
   const stdout = await runGit(workspaceRoot, ['worktree', 'list', '--porcelain'])
   for (const entry of parseWorktreePorcelain(stdout)) {
     if (entry.prunable || entry.branch !== branch)
@@ -135,6 +135,36 @@ export async function ensureWorktree(opts: WorktreeOpts): Promise<string> {
   return worktreePath
 }
 
+/**
+ * 接管方重建 worktree：分支已在 origin 上，本机从远端 checkout。
+ * `-B` 让本地同名残留分支直接对齐远端（发送方移交前已校验全部 push）。
+ */
+export async function ensureWorktreeFromRemote(opts: WorktreeOpts): Promise<string> {
+  const { workspaceRoot, branch } = opts
+  const worktreePath = path.resolve(opts.worktreePath)
+
+  await runGit(workspaceRoot, ['fetch', 'origin', branch], `拉取远端分支 ${branch}`)
+
+  // ① 已经有 live worktree → 复用，不动模板路径
+  const live = await findLiveWorktreeForBranch(workspaceRoot, branch)
+  if (live)
+    return live
+
+  // ② 模板路径被垃圾目录占着 → kill + 删，否则 add 撞路径
+  if (await pathExists(worktreePath)) {
+    killProcessesUsingWorktree(worktreePath)
+    await removeWorktreeDir(workspaceRoot, worktreePath)
+  }
+
+  await fsp.mkdir(path.dirname(worktreePath), { recursive: true })
+  await runGit(
+    workspaceRoot,
+    ['worktree', 'add', '-B', branch, worktreePath, `origin/${branch}`],
+    'git worktree add',
+  )
+  return worktreePath
+}
+
 /**
  * 删除一个 worktree 目录并清掉 git 侧注册。
  *